'''Ontario Hydro''', established in 1906 as the '''Hydro-Electric Power Commission of Ontario''', was a publicly owned electricity utility in the Province of Ontario
. It was formed to build transmission lines to supply municipal utilities with electricity generated by private companies already operating at Niagara Falls, Ontario|Niagara Falls
, and soon developed its own generation resources by buying private generation stations and becoming a major designer and builder of new stations. As most of the readily developed hydroelectricity|hydroelectric
sites became exploited, the corporation expanded into building coal
-fired generation and then nuclear power|nuclear-powered
facilities. Renamed as "Ontario Hydro" in 1974, by the 1990s it had become one of the largest, fully integrated electricity
corporations in North America.